Flutter Wave polarity on Sruface ECG and Endocardial activation in Typical counter clockwise atrial flutter

To analyze the endocardial activation of typical counter clock wise atrial flutter (CCW). A retrospective study of 24 cases admitted over a period of 5 years for atrial flutter ablation at St. Georges Hosptial, London. The electrophysiological study were reviewd from optical disc and right atrial activation analyzed in all cases of typical CCW atrial flutter. In CCW atrial flutter the negative flutter wave in inferior leads represent lateral and anterior right atrial activation while descending limb represents septal activation.